At the heart of the meeting will be a discussion about contaminated disposal facilities, a controversial clean-up option that would try to wall off contaminated sediments in the river instead of spending more money to dredge the sediments and haul them to landfills. The EPA is considering installing confined disposal facilities at Terminal 4 near the St. Johns Bridge, the upper end of Swan Island Lagoon and offshore of the Arkema site just south of the Willamette Railroad Bridge.

The federal government added the Portland Harbor to its national priority list of highly contaminated properties in 2000. Because of more than a century of industrial use, water and sediment along the harbor are contaminated with toxic industrial chemicals, from the pesticide DDT to polychlorinated biphenyls. PCBs, a former industrial insulator and probable carcinogen, are the main villain.

The Port of Portland, which would own the Terminal 4 CDF, did some
work, at the EPA's behest, several years ago to determine the feasibility of building the container. That work is not ongoing currently.

"Cleanup will likely require more than one option, as there is no one standalone solution," said Josh Thomas, a spokesman for the Port of Portland. The EPA could determine that CDFs are not feasible in some locations, including Terminal 4, Thomas said, but the agencies won't know until next year.

Opponents of CDFs say that the containers risk leaking back into the river long-term and that the one proposed for the Port's Terminal 4 would harm current sturgeon habitat. EPA representatives will address those concerns in tonight's meeting. The agency also has an extensive website that answers questions about the safety of the containers.

If the EPA decides to use CDFs, the agency would test all sediment before sending it to the containers. Some sediment won't qualify for inclusion in the Terminal 4 CDF.

The EPA expects a final plan for Portland harbor by 2014 at the earliest -- 14 years after the Superfund designation. Tonight's meeting begins at 5 p.m. at the BES Water Lab near Cathedral Park, 6543 North Burlington Avenue.